Mercury–fluorine interactions: a matrix isolation investigation of Hg⋯F2, HgF2 and HgF4 in argon matrices

HgF(2) and Hg have been trapped in dilute F(2)/Ar and neat F(2) matrices, subjected to UV-Vis and vac-UV photolysis and annealing, with the products identified by FTIR, UV-Vis-NIR and Hg L(3)-edge XAFS spectroscopic techniques. Whilst there was no convincing evidence for the formation of HgF(4) under our argon matrix isolation conditions, a new Hg...F(2) complex was identified and subsequent photolysis yielded HgF(2) very cleanly. Hg L(3)-edge EXAFS has provided the first experimental value of 1.94(2) A for the Hg-F bond length in HgF(2), which is in excellent agreement with the computational values incorporating relativistic effects.